JP 2000-59387 A and JP 2001-203806 A disclose a method of assigning an IP address to a node such as a computer in accordance with a DHCP (Dynamic Host Configuration Protocol).
There are provided a plurality of servers, each being provided with a specific function, such as a DHCP server for assigning an IP address to each node in a network in accordance with the DHCP, are installed in a single network so as to provide redundancy, thereby improving reliability of the servers.
However, for example, in providing redundancy for the DHCP servers, information indicating the correlation between an address and a node and the like is required to be managed so as not to generate any inconsistency among a plurality of servers.
However, it is not always easy to manage information so as not to generate any inconsistency among a plurality of servers.